Dual-type mobile terminals have the benefit of enabling the user to choose the type of network over which he wishes to connect in order to establish his communication, such as in order to adapt to the type of network that is accessible (particularly when one of the networks is inaccessible) or for subscription-related reasons, as a transfer over a WiFi network may prove to be more economical than a transfer over a cellular network, which requires a subscription.
In practice, however, the benefit for the user of being able to choose between two types of networks may prove to be problematic, because when establishing communication, the user must always select his terminal's operating mode, which may become tedious in the medium to long term.
Solutions have been proposed in order to reduce the steps performed by the user. One example is French patent application FR 2 866 184, which proposes selecting the network that is best-suited for a communication based on the performance of the networks provided to the terminal by access points, with the terminal making the choice based on predetermined criteria.
Such a solution is entirely satisfactory for some particular uses, particularly when the recipients of the calls made from the terminal all belong to the same category, covered by a single fixed price paid by the subscriber, or by his employer in the circumstances of a business telephony service.
However, it has become apparent that many users whose employer gives them access to a business telephony service use their terminal to make private calls. Although many employers in principle see no drawback to this practice, some feel that the use of the business's network resources by their employees for private purposes must not be encouraged. Call control and/or filtering policies may be instituted, but besides being disliked by employees, they require powerful (and as a result, expensive) analysis and/or filtering means.
No known solutions make it possible to compensate for this drawback: whether the user himself selects the type of network from his terminal, or whether this is done automatically by the terminal in accordance with the operating mode described in the aforementioned patent application, it may prove ineffective when the employer has instituted filters for certain call numbers, so that dual mode loses its attractiveness.